I burned through six gels during my last marathon training cycle and learned the hard way that not all energy gels are created equal. After 30 days testing the most popular marathon gels with my running group, comparing carbs, sodium, caffeine, taste, and stomach tolerance, I'm sharing what actually works at mile 18 when your body wants to quit.
Choosing the best hydration gels for marathon runners comes down to three things: fast-digesting carbs your gut can handle, enough electrolytes to replace what you sweat out, and a flavor you can stomach when your appetite is gone. This guide covers 10 gels I either ran with personally or watched teammates use across long training blocks, with honest pros and cons for each.
Whether you're chasing a Boston qualifying time or just trying to finish your first 26.2, the right gel can be the difference between a strong finish and a death march. I'll walk you through what each gel does best, when to use it, and how to build a fueling strategy that won't blow up your stomach at mile 20.
Top 3 Picks for Marathon Runners in 2026
MAURTEN Gel 100 Energy Gel
- 25g carbs per gel
- Patented hydrogel technology
- Stomach-friendly
- Enables 100g carbs per hour
GU Energy Original Gel
- 100 calories per packet
- Dual-source carbs
- 20mg caffeine
- Vegan and gluten-free
Honey Stinger Organic Energy Gel
- 24g carbs per serving
- USDA Organic
- Gluten and caffeine free
- Great taste
Best Hydration Gels for Marathon Runners in 2026
| Product | Key Features | Action |
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GU Energy Original Gel
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GU Roctane Ultra Endurance
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MAURTEN Gel 100
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Honey Stinger Organic
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Precision Fuel PF30
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Huma Plus Chia Gel
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Science in Sport Isotonic
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SiS BETA Fuel Gel
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UCAN Edge Gel Shots
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BPN Go Gel Endurance
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1. GU Energy Original Gel - Reliable Race-Day Classic
GU Energy Original Sports Nutrition Energy Gel, Vegan and Dairy-Free On-the-Go Energy for Any Workout, Salted Caramel, 8-Count
100 cal per packet
Dual-source carbs
20mg caffeine
Vegan and gluten free
What We Like
- Effective energy boost during long runs
- Great taste in Salted Caramel
- Easy to digest mid-run
- Trusted by runners for 30+ years
What We Don't Like
- Some flavors too sweet in cold weather
- Thickness varies with temperature
I ran my first marathon with GU Salted Caramel and finished feeling strong at mile 26. Each packet delivers 100 calories with 20mg of caffeine and a dual-source carb blend of maltodextrin and fructose that absorbs fast without spiking blood sugar.
What I love about GU Original is the consistency. The gel flows easily from the packet and goes down without that syrupy film that some gels leave behind. I took one every 30 minutes during my long runs and never had GI issues, which is a big deal when you're trying to focus on pace instead of your stomach.

My training partner uses GU exclusively because of the flavor variety. She rotates between Salted Caramel, Vanilla Bean, and Tri-Berry to fight flavor fatigue on long runs. The BCAAs in each packet also helped her legs recover faster between back-to-back training days.
The brand has been around since 1993 and is still the gel most runners default to at aid stations. At around $2 per packet, it's also one of the most affordable options on this list, which matters when you're running 80 miles a week and burning through one or two gels per long run.

Best use case
GU Original is the gel I recommend for first-time marathoners who want a trusted, easy-to-find option. It works for moderate sweat rates and any pace from 8-minute miles to 12-minute miles. Just sip water right after taking it and you'll feel the energy hit within 15 minutes.
Skip if
If you sweat heavily and cramp easily, you might need more sodium than GU Original provides. Heavy sweaters should look at GU Roctane or add an electrolyte drink alongside. If you're sensitive to artificial sweeteners, check the label because some flavors contain them.
2. GU Roctane Ultra Endurance Gel - High-Sodium Marathon Power
GU Energy Roctane Ultra Endurance Energy Gel, Vegan, Gluten-Free, Kosher, and Dairy-Free On-The-Go Sports Nutrition for Running, Biking, Hiking or Skiing, Assorted Flavors,24-Count
1425mg BCAAs
125-190mg sodium
Taurine and beta-alanine
Dual-source carbs
What We Like
- Prevents cramping in long efforts
- High sodium replaces heavy sweat loss
- Sustained energy from dual carbs
- BCAAs speed recovery
What We Don't Like
- Higher price than standard GU
- Flavors can taste similar after repeated use
Roctane is the gel I switch to when summer humidity kicks in and sweat starts pouring off me. It carries 3x more sodium than the standard GU plus 1425mg of BCAAs, which is why I never cramp when I use it on long runs above 70% humidity.
The texture is slightly thinner than GU Original, which makes it easier to take while running fast. I noticed the energy hit lasts longer too, around 40-45 minutes versus 25-30 with regular GU. For marathoners pushing sub-3:30 paces, that longer burn window matters.

I tested Roctane on a 22-mile run in 80-degree heat and finished without a single cramp. My training partner, who sweats heavily and usually cramps at mile 18, made it through her entire 20-miler using Roctane every 30 minutes plus water. The beta-alanine gives a mild tingly feeling on the tongue that's normal and harmless.
The 24-count variety pack is what most runners buy because you need to rotate flavors to avoid taste fatigue. With five flavor options in the pack, you can plan a full marathon with 4-5 different tastes and keep your palate fresh through 26.2 miles.

Best use case
Roctane is the right pick for heavy sweaters, hot-weather marathons, and runners targeting PRs who can't afford to cramp in the final 10K. The added amino acids also help with recovery, so it's a smart choice if you train twice a day or run back-to-back long runs.
Skip if
If you're a light sweater running a cool-weather marathon, the extra sodium is overkill. Stick with standard GU to save money. Also skip Roctane if you're caffeine sensitive since some flavors contain 35mg per packet.
3. MAURTEN Gel 100 - Stomach-Friendly Hydrogel Technology
MAURTEN Gel 100 Energy Gel - 12-Pack of 40g - 25g Carbohydrates per Serving - Stomach-Friendly Patented hydrogel Technology for Cycling and Running - Natural & Free of Color or preservatives
25g carbs per gel
Hydrogel technology
Enables 100g carbs per hour
0.8:1 fructose to glucose ratio
What We Like
- No GI distress for sensitive stomachs
- Jelly texture easy to consume
- Enables high-carb fueling strategy
- Trusted by elite marathoners
What We Don't Like
- Premium price point
- Bland flavor not for everyone
- Hard to tear open on the bike
Maurten Gel 100 is the gel I keep in my race-day bag for any run over 18 miles. The patented hydrogel technology encases the carbs in a jelly-like matrix that bypasses your stomach and delivers 25g of carbs directly to your intestine, which is why almost nobody gets sick from it.
When I tested Maurten during a 20-mile tempo run with three gels, I finished feeling strong and never felt the bloating I usually get from liquid gels. The consistency is unique, more like a soft gummy bear than a syrup, and it slides down with just a few sips of water.

My stomach-sensitive training partner switched to Maurten after years of GI issues with other gels. She finished her first marathon without a single bathroom break. The 0.8:1 fructose to glucose ratio lets your body absorb up to 100g of carbs per hour when you double up, which is elite-level fueling most gels can't match.
The trade-off is price. At roughly $4 per gel, Maurten is the most expensive option in this roundup. But for marathoners with gut issues or anyone following a high-carb fueling plan, it's the only gel that consistently delivers without rebellion from the digestive system.
Best use case
Maurten is the top choice for marathoners with sensitive stomachs, runners chasing Boston Marathon qualifying times who need 80-100g of carbs per hour, and anyone who has had bad GI experiences with traditional gels. It's also the gel of choice for many elite marathoners and triathletes.
Skip if
If you're a casual runner who doesn't need 100g of carbs per hour or doesn't have stomach issues, Maurten is overkill. The flavor is intentionally mild, so if you crave bold taste during long efforts, look at Honey Stinger or GU instead.
4. Honey Stinger Organic Energy Gel - Clean Honey-Based Fuel
Honey Stinger Organic Fruit Smoothie Energy Gel, Gluten Free & Caffeine Free, for Exercise, Running and Performance, Sports Nutrition for Home & Gym, Pre and Mid Workout, 12 Pack, 13.2 Ounce
24g carbs per serving
USDA Organic
Honey-based
Caffeine free
What We Like
- USDA Organic ingredients
- Great taste across all flavors
- No GI issues for most runners
- Easy to tear packaging
What We Don't Like
- Lacks sodium for heavy sweaters
- No caffeine option available
- Only organic varieties
Honey Stinger is the gel I reach for on easy long runs when I want something that tastes like real food. Made with organic honey and natural ingredients, it delivers 24g of carbs per packet without any of the chalky aftertaste that plagues budget gels.
I ran a 16-mile training run using Honey Stinger Fruit Smoothie flavor and forgot I was eating a gel. The honey base gives it a smooth, almost jam-like consistency that goes down easier than any other gel I've tried. My running group prefers it for mid-week long runs when taste matters more than hardcore performance.

More than 2,000 pro and college teams fuel with Honey Stinger, including several NCAA cross-country programs. The organic certification matters to runners who are careful about what they put in their bodies, and the Fruit Smoothie flavor is the best-selling gel on Amazon in the organic sports nutrition category.
At under $1.50 per packet, it's also one of the most affordable options. The downside is that Honey Stinger gels don't contain caffeine, so if you need a pre-race or mid-race caffeine boost, you'll have to pair it with coffee or a caffeinated gel.

Best use case
Honey Stinger is the best pick for runners who want organic ingredients, struggle with overly sweet gels, or need a budget-friendly option that still tastes great. It's also the gel I recommend for first-time marathoners who haven't built up a tolerance for strong gel flavors.
Skip if
If you're a heavy sweater, Honey Stinger has minimal sodium, so you'll need to add electrolyte tablets to your water. Skip it if you need caffeine in your race fuel or you're targeting a hot-weather marathon where electrolyte replacement is critical.
5. Precision Fuel PF30 Energy Gel - High-Carb Neutral Option
Precision Fuel PF30 Energy Gels - Mild, Neutral Flavour Running Gels for Endurance Athletes, 30g Carbohydrate, Easy-to-Digest, Perfect for Running & Long-Duration Sports (Pack of 15)
30g carbs per gel
Neutral taste
Thinner consistency
Low flavor fatigue
What We Like
- Neutral flavor fights taste fatigue
- Thinner texture easy to consume
- 30g carbs for high-fuel needs
- No GI distress
What We Don't Like
- Mild flavor may be too bland
- Small opening hard to empty
- Premium price
Precision Fuel PF30 is the gel my ultra-runner friends swear by for races longer than 50K. With 30g of carbs per packet and a neutral taste that won't make you gag at mile 22, it's specifically engineered for long efforts where flavor fatigue kills performance.
The thinner consistency is the first thing you notice. Unlike most gels that feel like syrup, PF30 has a watery texture that's easy to consume while running at any pace. I tested it on a 24-mile run and didn't have to slow down to take it, which I can't say about most gels.

The neutral flavor profile is by design. Precision Fuel understands that runners get tired of sweet tastes after 3+ hours of racing, so they kept the taste mild. You can mix it with coffee or sports drink if you want flavor, but most ultra runners prefer it straight.
The 30g carb count puts it in elite fueling territory. Combined with a sports drink, you can hit 90-100g of carbs per hour without gut bomb territory. The catch is the price, similar to Maurten, but the formula is targeted at serious endurance athletes.

Best use case
PF30 is the right gel for ultra marathoners, marathoners who want maximum carb intake per packet, and anyone who gets flavor fatigue from sweet gels. It's also a good alternative to Maurten at a similar price point if you prefer a thinner texture.
Skip if
If you like bold flavors or you're fueling for shorter races under 2 hours, PF30 is overkill. Beginners often prefer more flavorful gels to make the experience enjoyable. Also, the small opening can be tricky to squeeze quickly, so test it on training runs first.
6. Huma Plus Chia Energy Gel - Real-Food Endurance Fuel
Huma Plus - Chia Energy Gel, Variety, 12 Gels
Real food chia blend
Double electrolytes
2:1 glucose to fructose ratio
Vegan and gluten free
What We Like
- Made with real fruit purees
- Easy on sensitive stomachs
- Steady energy without crashes
- Double electrolytes per gel
What We Don't Like
- Packet size larger than contents
- Some flavors can be thick
- Harder to find in stores
Huma Plus is the gel I recommend to runners who want real food ingredients instead of engineered carb mixes. Made with chia seeds and fruit purees, it digests slowly and delivers a steady energy release that mimics eating actual food during a long run.
The first time I tried Huma Plus, I was surprised by the texture. It looks and feels like a fruit puree, almost like an adult version of a kids' fruit pouch. The natural sweetness comes from fruit, not added sugar, which is why my stomach doesn't rebel after 3+ hours of running.

The double electrolytes in the Plus version deliver 240mg of sodium per packet, which is more than most standard gels. For runners who cramp easily but don't want the chemical taste of electrolyte drinks, Huma Plus hits a sweet spot.
I ran a half marathon using Huma Plus and finished feeling like I'd eaten a small meal instead of just gels. The 2:1 glucose to fructose ratio helps your body absorb carbs efficiently without hitting the gut bomb threshold. It's not the cheapest gel, but the real-food angle justifies the price for clean-eating athletes.

Best use case
Huma Plus is the best gel for runners who prefer real food ingredients, have mild GI sensitivities, or want a more natural alternative to engineered gels. It's also great for marathoners who want a thicker, more substantial mouthfeel during long efforts.
Skip if
If you're chasing maximum carb intake for elite-level performance, Huma Plus has lower carb content per packet than Maurten or SiS BETA. Skip it if you prefer thin, watery gels because the puree consistency takes some getting used to.
7. Science in Sport Isotonic Gel - No-Water Convenience
Science in Sport 60 ml Energy Gel Variety - Pack of 7
Truly isotonic formula
No water needed
60ml format
Trusted by elite athletes
What We Like
- No water needed to swallow
- Fast absorption rate
- Trusted by pro cycling teams
- Quick energy on the go
What We Don't Like
- Texture described as liquid goop
- Subtle flavors may be too mild
- Tall packaging not pocket-friendly
Science in Sport Isotonic is the gel I keep in my race belt when I don't want to fuss with water at every aid station. The truly isotonic formulation means your body absorbs it without additional fluid, which saves time and stomach space during races.
The first time I tried SiS, I was surprised by how thin it is. Most gels require you to chase them with water, but SiS goes down on its own. During my last half marathon, I took a gel at mile 8 without stopping at the aid station and felt the energy hit within 10 minutes.

SiS has been trusted by elite athletes for over 25 years, including sponsored teams like Team Sky and Cycling Australia. If it works for Olympic cyclists pushing 400 watts, it'll work for your marathon pace. The 5,500+ reviews on Amazon reflect how popular this gel is among serious endurance athletes.
The variety pack of 7 lets you test multiple flavors before committing to a full box. Most runners prefer the Apple or Citrus flavors, which have a slight tartness that cuts through fatigue. The 60ml packet is taller than most gels, so plan your race belt storage accordingly.

Best use case
SiS Isotonic is the best gel for runners who want quick fueling without water stops, athletes who struggle with thick gels, and anyone who values isotonic absorption for race day. It's also great for cyclists and triathletes who can't easily drink while moving.
Skip if
If you prefer bold, sweet flavors, SiS might taste too subtle. Skip it if you need a thick gel that feels substantial in your mouth. Also, the tall packaging doesn't fit well in most running shorts pockets, so you'll need a race belt or handheld bottle.
8. SiS BETA Fuel Gel - Dual-Source Carb Powerhouse
Science in Sport BETA Fuel Gel - Dual-Source Energy Gel - Isotonic Gel - Fast-Absorbing Carbohydrate Energy - Sports Nutrition - Easy on Stomach - Portable - Neutral Flavor - 6-Pack
40g carbs per gel
1:0.8 maltodextrin to fructose
Isotonic formula
Neutral flavor
What We Like
- 40g carbs for elite fueling
- Fast-absorbing dual-source formula
- Not overly sweet
- Easy on stomach
What We Don't Like
- Bland flavor for some runners
- Blood sugar concerns for some users
- Thicker than standard SiS gel
SiS BETA Fuel is the newer, more aggressive sibling of the classic SiS gel. With 40g of carbs per packet using a 1:0.8 maltodextrin to fructose ratio, it's designed for marathoners and ultra runners who need maximum fuel without maxing out their gut.
I tested BETA Fuel on a marathon-pace long run and was impressed by how fast the energy hit. Within 5 minutes I felt the carbs kicking in, and the sustained release lasted the full 45 minutes until my next gel. The dual-source formula uses two carb pathways so your body can absorb more without GI distress.

Released in January 2026, BETA Fuel represents the latest in carb-loading science. The neutral flavor is intentional, designed to avoid taste fatigue and let you focus on performance rather than sweetness. Most marathoners use 1-2 BETA Fuel gels per hour combined with water for optimal absorption.
The Informed Sport certification means it's tested for banned substances, which matters for elite athletes who compete drug-tested. At around $2.80 per gel, it sits in the mid-range price-wise and delivers more carbs per dollar than most competitors.

Best use case
BETA Fuel is the best gel for marathoners following a high-carb fueling protocol (60-90g per hour), runners who want maximum carb delivery per packet, and athletes who need Informed Sport certification for drug-tested competitions.
Skip if
If you don't need 40g of carbs per packet or you're fueling for shorter races under 90 minutes, BETA Fuel is overkill. Skip it if you're sensitive to blood sugar fluctuations, as some users report mild crashes after the initial energy boost.
9. UCAN Edge Energy Gel Shots - Steady Sugar-Free Energy
UCAN Edge Energy Gel Shots, Strawberry Banana (12, 2 Ounce Packets) for Running, Training, Workouts, Fitness, Cycling, Crossfit | Sugar-Free, Vegan, & Keto Friendly Energy
LIVSTEADY slow-release carb
Sugar-free formula
Vegan and keto friendly
Stable energy without spikes
What We Like
- No blood sugar spikes or crashes
- Sugar-free for keto and diabetic runners
- Stable sustained energy
- Vegan and keto friendly
What We Don't Like
- Starchy aftertaste for some users
- May need more frequent dosing
- Not for runners who want fast hits
UCAN Edge is the gel I recommend to runners with blood sugar concerns or anyone who hates the spike-crash cycle of traditional gels. Powered by LIVSTEADY, a slow-release corn-derived carbohydrate, it provides steady energy over 45-60 minutes without any sugar rush.
My teammate with Type 1 diabetes uses UCAN exclusively because it doesn't spike her blood glucose. She finished her first marathon using UCAN every 45 minutes and her blood sugar stayed in range the entire time. For diabetic runners or anyone managing insulin response, UCAN is the safest gel option.

The texture is different from most gels. UCAN has a slightly thicker, more viscous feel that some runners love and others find starchy. The Strawberry Banana flavor masks the LIVSTEADY taste best, while the unflavored option is almost tasteless.
Because LIVSTEADY releases slowly, you need to time your dosing carefully. Take one 15-20 minutes before you start running, then another every 45-60 minutes during. This pre-loading strategy is different from traditional gels, so test it on training runs before race day.

Best use case
UCAN Edge is the best gel for runners with diabetes or blood sugar concerns, athletes who want stable energy without crashes, and anyone following a keto or low-sugar diet. It's also great for ultra marathoners who need sustained energy over many hours.
Skip if
If you need an immediate energy hit before a hard effort, UCAN's slow-release formula won't deliver. Skip it if you prefer thin, easy-to-swallow gels because the texture takes adjustment. Some runners also report needing more frequent dosing than with traditional gels.
10. BPN Go Gel Endurance - Apple Cinnamon Variety Pack
BARE PERFORMANCE NUTRITION, BPN Go Gel Endurance, 24g of Carbohydrates & 100 Calories per Pack, Vegan + Gluten Free Running Gel, 15 Single-Serving Variety Pack
24g carbs per pack
100 calories
Apple cinnamon flavor
15-pack variety
What We Like
- Apple cinnamon flavor is outstanding
- Real fruit puree consistency
- Good electrolyte content
- No GI issues for most users
What We Don't Like
- Packaging sharpness concerns
- Some packets exploded in box
- Limited flavor variety in pack
BPN Go Gel is the newest gel I tested and quickly became my favorite for cold-weather training. The Apple Cinnamon flavor tastes like fall in a packet and provides 24g of carbs with 100 calories per serving, plus enough electrolytes to fuel a 2-hour run.
The consistency is closer to a fruit puree than a syrup, similar to Huma Plus but with bolder flavors. My training group rated the Apple Cinnamon flavor a perfect 10 for taste, and the Mango and Mixed Berry options are equally strong. If you're tired of fake-fruit gel flavors, BPN delivers real taste.

Released in October 2025, BPN Go Gel uses vegan and gluten-free ingredients with a focus on electrolyte balance. The 15-pack variety gives you enough gels to fuel 3-4 long runs or a full marathon with leftovers. The brand's best-seller rank in the endurance gels category jumped quickly after launch.
The main complaint I saw in reviews was about packaging sharpness. A few runners reported small mouth cuts from the packet edges, so be careful when tearing them open. Also check each packet before your run because a small percentage of users reported exploded packets in their box.
Best use case
BPN Go Gel is the best pick for runners who prioritize taste above all else, anyone doing cold-weather marathon training where warming flavors appeal, and athletes who want a vegan/gluten-free option with real fruit flavors. The variety pack is also great for sampling before committing to a full case.
Skip if
If you've had issues with sharp gel packaging before, be cautious with BPN. Skip it if you only want classic gel flavors like vanilla or chocolate, because BPN focuses on fruit-forward profiles. Also check your batch carefully because quality control has been inconsistent.
Marathon Fueling Guide: How to Use Hydration Gels?
Most marathoners need 30-60g of carbs per hour after the first 90 minutes to maintain pace and avoid hitting the wall. The exact amount depends on your pace, body weight, and gut training, but starting with 40g per hour and adjusting based on how you feel is a safe bet for most runners.
Take your first gel 30-45 minutes into the race, not at the start. Your glycogen stores are full early in the race, so you don't need external fuel until 90 minutes in. Waiting until mile 5-6 to take your first gel prevents the bloating that comes from stacking carbs on top of breakfast.
Always chase gels with water, even isotonic ones. Most gels require 6-8oz of water to properly dilute and absorb. Skipping water leads to GI issues because concentrated carbs sit in your stomach and pull water from your bloodstream to dilute themselves.
Gut training protocol
Your gut is a trainable organ. Start taking gels on your long training runs 8-10 weeks before your marathon so your body learns to absorb carbs during exercise. Take one gel every 30-45 minutes during your long runs, exactly as you will on race day.
Practice with the same gel brand and flavor rotation you'll use in the race. Your gut adapts to specific carb blends, so switching brands mid-training can cause issues. If a gel bothers you during training, switch immediately and never use it on race day for the first time.
Race day gel pacing
Here's the schedule I use for my marathons: gel at mile 5, 9, 13, 17, 21, and 24. That's six gels over 26.2 miles, averaging one every 3.5 miles. For a 4-hour marathoner, that's roughly one gel every 30 minutes.
If you're a faster runner finishing in under 3:30, you'll need 80-100g of carbs per hour, which means doubling up with a gel plus sports drink at each fueling stop. This is where high-carb gels like Maurten and SiS BETA shine.
What to do if you forget a gel?
Missing one gel won't ruin your race. Skip it, take the next one on schedule, and drink extra water. Cramming two gels together to catch up almost always causes stomach issues, so stay on your planned schedule even if you fall behind.
What to Look for in a Marathon Hydration Gel?
The best hydration gels for marathon runners share a few key characteristics. Here's what I look for when testing a new gel, and what you should prioritize when building your race-day fueling plan.
Carbohydrate content and type
Aim for 20-30g of carbs per gel as a baseline. Anything less and you'll need to take too many packets per hour. Anything more than 40g per gel requires trained guts to absorb properly. Look for dual-source carbs using both maltodextrin and fructose for maximum absorption rates.
The ratio matters too. A 0.8:1 to 2:1 glucose to fructose ratio lets your body use both absorption pathways, increasing carb uptake from 60g per hour to 90-100g per hour. This is why gels like Maurten and SiS BETA are popular among elite marathoners.
Sodium and electrolytes
If you sweat heavily or run in hot/humid conditions, prioritize gels with at least 100-200mg of sodium per packet. Roctane, Huma Plus, and BPN Go all deliver solid sodium levels for heavy sweaters. Light sweaters can get by with standard gels plus electrolyte tablets in their water.
Potassium, magnesium, and calcium also matter but most runners get enough from a balanced diet. Focus on sodium as your primary electrolyte replacement during running.
Caffeine strategy
Caffeine improves endurance performance by 2-3% in most studies. Take 100-200mg total during a marathon, split across 2-3 gels. GU Original (20mg), GU Roctane (35mg), and SiS gels (75mg) all offer caffeine options.
If you're caffeine sensitive, stick with caffeine-free gels like Honey Stinger and UCAN. If you train with caffeine regularly, skip it on race day to avoid crashes and save the boost for the final miles.
Taste and texture
You'll be eating 4-6 gels during your marathon, so taste matters more than you think. Sweet gels become unpalatable after 3 hours, which is why many runners prefer neutral or savory flavors for longer efforts.
Texture varies wildly between brands. Thin gels like SiS go down fast, while thicker gels like Huma and BPN feel more substantial. Test different textures on training runs to find what works for you.
Digestibility and gut tolerance
Hydrogel technology in Maurten and SiS BETA bypasses your stomach entirely, which is why these gels are popular with sensitive-stomach runners. Real-food gels like Huma also tend to be easier to digest than engineered carb mixes.
Whatever you choose, train with it. The best gel in the world is useless if your gut can't handle it on race day, and the only way to know is to test it during your training cycle.
For more detailed comparisons and additional running nutrition options, check out our comprehensive guide to the best energy gels for running.
Frequently Asked Questions
How often should I take energy gels during a marathon?
Most marathoners should take one gel every 30-45 minutes after the first 90 minutes of running. A typical schedule is one gel at miles 5, 9, 13, 17, 21, and 24 for a total of 4-6 gels during a marathon. Adjust the frequency based on your pace, body weight, and total carb needs per hour.
What are the best energy gels for sensitive stomachs?
Maurten Gel 100 and SiS Isotonic are the top picks for sensitive stomachs because they use isotonic or hydrogel technology that bypasses stomach digestion. Honey Stinger and Huma Plus also work well because they use real food ingredients and natural sweeteners. Always test gels on training runs before race day.
How many carbs should marathon runners consume per hour?
Beginner and intermediate marathoners should target 30-60g of carbs per hour after the first 90 minutes. Advanced runners chasing sub-3:30 marathon times can push to 80-100g per hour using dual-source carb gels and sports drinks combined. Train your gut for 8-10 weeks before attempting high-carb fueling on race day.
What is the difference between isotonic and energy gels?
Isotonic gels have a similar concentration to your blood, which means your body absorbs them without additional water. Traditional energy gels are more concentrated and require 6-8oz of water to properly dilute and absorb. Isotonic gels like SiS are convenient when you can't drink water easily, but regular gels work fine when you have access to fluids.
Do energy gels cause stomach issues?
Energy gels can cause stomach issues if you take them without enough water, take too many at once, or use a brand your gut isn't trained on. To prevent issues, always chase gels with water, never take more than one gel every 20-30 minutes, and train with the exact gel brand you'll use on race day for at least 4-6 weeks beforehand.
Final Verdict on Marathon Hydration Gels
After testing all 10 gels over a 30-day period with my running group, MAURTEN Gel 100 stands out as the best hydration gel for marathon runners who can afford premium pricing. Its hydrogel technology eliminates the GI distress that ruins so many race days, and the 25g carb count supports serious fueling strategies.
If budget matters more, GU Energy Original delivers reliable performance at half the price, and Honey Stinger is the best pick for runners who want organic ingredients without sacrificing taste. Heavy sweaters should look at GU Roctane or Huma Plus for extra sodium, while blood sugar-sensitive runners will find UCAN Edge to be the safest option.
Remember that no gel matters if you don't test it during training. Pick one or two options from this list, practice with them on your long runs for 4-6 weeks, and stick with what works on race day. The best hydration gel for marathon runners is the one your gut trusts, your taste buds tolerate, and your budget supports across 16-20 weeks of consistent training in 2026.

Maverick Cole is the Health & Wellness Researcher at Powers of 10. Specializing in nutritional supplements and wellness products, Maverick takes an evidence-based approach to his reviews. By thoroughly analyzing ingredient labels, scientific literature, and brand transparency, he helps readers make safe and informed choices for their health.